Computer-assisted prediction of the instability of Colles' fractures.

Many Colles' fractures are unstable and have a tendency to redisplace when immobilised in plaster. In an earlier study, we found a high correlation between several parameters from the initial radiographs in 267 patients and the anatomical end results. The predictive power of a new computer programme designed from the data of these patients was investigated in a further group of 107 Colles' fractures. Prediction of the final radiological position was good, especially in the least and moderately displaced fractures. We have found that the initial radial shortening, the type of fracture according to Lidström's classification, and the age of the patients have the greatest value in predicting whether a Colles' fracture will displace to an unacceptable degree.